Coal companies have paid millions of dollars to Johns Hopkins Medical Institutions over the last decade for medical opinions that have been used to deny hundreds of ailing mine workers meager black lung benefits, a yearlong investigation by ABC News and the Center for Public Integrity found.

"It is a total, national disgrace," said Sen. Jay Rockefeller, D-W.Va., of the findings. "The deck is stacked in theory and in practice against coal miners, men and women, and it is tragic."

The head of the Hopkins unit that interprets X-rays in black lung cases, Dr. Paul Wheeler, found not a single case of severe black lung in the more than 1,500 cases decided since 2000 in which he offered an opinion, a review by ABC News and the Center found. In recent court testimony, Wheeler said the last time he recalled finding a case of severe black lung, a finding that would automatically qualify a miner for benefits under a special federal program, was in "the 1970's or the early 80's."

"That's my opinion, and I have a perfect right to my opinion," Wheeler told ABC News in a lengthy interview in which he defended his track record. For his work, coal companies pay Hopkins $750 for each X-ray he reads for black lung, about ten times the amount miners typically pay their doctors.

Hopkins said it has no reason to doubt Wheeler's findings, calling him "an established radiologist in good standing in his field."

"If I had my hands around his neck, I'd have squeezed it," said Michael "Steve" Day, whose $1,000-a-month black lung benefits were cut off after a judge denied his claim in 2011, relying in part on Wheeler's testimony in 2009 that Day did not have severe black lung. Day, who spent more than 30 years working in coal mines, had been diagnosed with black lung by his own doctors and the Veterans Administration.

Wheeler said he had "no idea" what happens to miners once he issues his opinions. "It would matter to me if I were wrong, and no one's proven to me that I'm wrong," he said.

But the joint investigation by ABC News and the Center for Public Integrity found that Wheeler has been wrong or mistaken in more than 100 cases in which autopsies or biopsies later found black lung after Wheeler had read the X-rays as negative. Such evidence is not available in the majority of cases.

"The doctor should not be working at Hopkins University or anywhere else," said Sen. Rockefeller after being told about Wheeler and the investigation's findings.

In his interview with ABC News, Wheeler said he considers black lung to be relatively rare and expressed concern that some miners might be trying to cheat the companies by falsely claiming to have black lung.

"That would seem inappropriate to me," he said.

Other experts in black lung disease told ABC News that Wheeler's medical views seem far outside the mainstream, and several bluntly questioned Wheeler's approach. Dr. Michael Brooks, a radiologist at the University of Kentucky who sees thousands of black lung cases, said Wheeler's results were "either a case of someone really having no idea of what they're doing or being willfully misleading. One of those two possibilities."